Cells are recognized as basic elements of the activities of life, as a result of which the measurement and study of cells has aroused great attention in scientific research and medical field. Cell measurements according to their principles and approaches may include but are not limited to biomechanics measurement, electrical measurements, motility and physicochemical property measurement. The common methods adapted are acknowledged as observation via microscope, electrochemical measurement and optical measurement. To be observed via microscope and optically measurement, the cells need to be labeled chemically or fluorescently, which in turn changes the original properties of cells to some degree. Besides, the operation process is complicated and the function is limited to one single purpose. On the contrary, electrochemical measurement doesn't require labeling and does less harm to cells, which makes it possible to continuously measure the cells in a naturally culturing and real-time way. Comparing with conventional chemical methods, electrochemical measurement comes with higher sensitivity and full automation.
In terms of electrochemical measurement, it is essential to position the cells for implementing precise in-situ single cell assay. Dielectrophoresis (DEP) is given prominence as a significant manipulation tool for the studies of cells, viruses, DNA in the field of life science.
Existent technologies concerning cell electrical measurement don't position the cells, on account of which the cells are scattered randomly in the measurement process. Consequently the efficiency and precision of the measurement is difficult to compliment. The situation is same with electroporation. Furthermore, the random cell distribution on the chip brings about high cell mortality rate and poor controllability.